Silica question


#1

Is all silica the same? Is the silica that comes out of a gold mine the same silica that is used in chromotapgrphy


#2

You need to buy a silica called SILICA 60 and then check mesh size. No bigger than 120 and no smaller than 20 in my personal opinion. Any other kind of silica I wouldn’t use.


#3

Can you enlighten us @Shadownaught

Edit: please and thank you!


#4

There is most certainly a huge difference in silica types. Particle size, shape, and pore geometry are the primary values.

The 60 in Silica 60, available at Carbon Chemistry :wink: , refers to 60angstrom pores. The Silica 60 is also 20-45 micron particle size for surface area and spherical, meaning round shape rather than odd shaped chunks, for improved flow.

Amorphous silica looks like chunks and although cheaper can often flow weird, especially under pressure like in HPLC or Flash Chromatography.

Purity would be a concern to some extent, but silica products are generally extremely pure unless you are buying crushed quartz rock.

Clays are alumina silicates with different functionality and synthetic magnesium silicate has the magnesium added in a controlled way. So there are a wide variety of functional silica products.